Floor-scraping machine.



- y A.. sem-Bm.

FLOOR SCRAFIKG HAGHINE. APLIOATIOI FILED lBB. 24, 1908.

Patented Feb. 2,1909.

Y To all whom it may concern:

\ NITED s'rATns-rATENT crimen.

i ALBERT SOHWENKE, OF KLEIN-WELSHEIM, NEAR SELIGENSTADT, GERMANY.

FLOOR-SCRAPING- IVIAGHINE.V

Beit known that I, ALBERT SCHWENKE, a subject of the German Emperor, residing at Klein-VVelsheim, 'near Seligenstadt, I-Iesse, in the Empireof Germany, manufacturer, have invented certain new and useful Improvements in Floor-Scraping Machines, of which the following is a full, clear, and exact description.

This invention has forits object an ape paratus intended for scraping, by means of sharp steel blades, floors of any kind but especially parquetry oors. The apparatus hitherto employed for this purpose usually consisted of a port-able frame, on which the steel blade (the knife) was rigidly mounted. The result of this arrangement was that when the apparatus was pushed forward by the movement of the operator, an uneven and very uncertain action of the knife took place. Attempts have also been made to arrange the knife blade so as to adjust itself, but all the arrangements hitherto provided for this purpose were such that the knife blade was weighted unevenly by the springs, and therefore also the pressure of the spring increased with the pressure exerted by the hand of the operator. In all thesearrangements in particular the blades were mounted in rigid bearings, so that they could not sufficiently yield to varying requirements.

Now this invention has for its object a parquetry floor scraping machine which is characterized by its not only being doubleacting and thus acting in both directions of travel, with a separate knife for each, but also by its having a quite peculiar arrangement'of springs by which the great advantage is attained that both knife blades are held to a certain extent oscillatingly be tween each two springs, and in consequence of this bear on the floor with an approxi-v mately constant'pressure and operate thereon uniformly.

The improved apparatus is shown in the accompanying drawings, `in which Figure 1 is a side view; and Fig. 2 a plan view.

As may be seen therefrom a broad roller 3, which is preferably provided with indiarubber treads 4, is Vmade portable by means of a fork 1 and an axle 2. This roller also serves for loading the device and is therefore made of suitable weight. Instead of this rigid system however two separate running Wheels mounted on the ends of the aXle 2V Specification of Letters Patent.

` Patented Feb. 2, 1909.

applicati@ siearebruary 24, 190s. semina. 417,351.

may also be provided, so that then the roller '3 only represents the loading weight. The fork 1 is also provided with pivots 5 and 6. Double elbow o r T-shaped knife holders 7 and 8 are pivotally arranged in these pivots 5 and 6, in such a way that they may both move up and down independently of one another. The scraping knives 9 and 10 are mounted on the knife holders. Two pairs of right arms or projections 11, 12, are also provided on the fork l against which arms, springs 13 and 14 bear. The other ends of the springs are placed on the knife holder 7 and spring pins 15 pass through the arms 11 but have a certain amount of free play in the holes of these arms, so that when the knife holder 7 turnsin the pivot 5 they can move forwards and backwards correspondingly in the arms 11. Exactly the same arrangement is adopted for the springs 14 which bear against the knife holder 8, the spring pins 18 of which have suflicient freedom of movement in the arms or projections The springs 13 and 14 will now hold the two knife blades 9 and 10 in a certain position which is adjusted Vby screw nuts 17 and 1S. In this condition of affairs the springs would press the knives harder on the iioor, the more obliquely the operator holds the machine. This would render the action uneven and in order to prevent this a third system of springs 19 is provided. These springs are so arranged that they bear with one end against the knife holder 7 and with the other against the' knife holder 8. Their spring pins 20 are mounted firmly in the knife holder 8 and have a suiiicient freedom of movement in the arms 21 which are formed in one piece with the knife holder 7. Nuts 22 are placed so far on the endsA -is moved forward, the knife 9, and when drawn backward, the knife l() are always held suspended each balanced between two springs. vA uniform and gentle action of the knives is thereby attained, so that even an unskilled operator can obtain excellent re` sults with the improved machine.

The entire apparatus may be conveniently inoved to and fro by means of a handle or shaft 23 and in the forward movement be held down at the rear and in the backward movement at the front, so far that corresponding thereto one or other of the knives, which in the normal position stand a little away from the floor, each time are depressed, and come into action.

l declare that what I claim is l. In a scraping machine for floors, a support frame, a plurality of scraping blades carried by said frame one in advance of the other and counterbalaneed spring means for positioning said blades.

2. ln a scraping machine for floors, a support frame, a plurality of scraping blades carried by said frame, one in advance of the other, a pair of spring devices acting upon each blade to position it, the two members of each pair of spring devices being arranged to eounterbalanee each other.

ln a scraping machine for floors, a snpport frame, two blade holders mounted upon said frame, scraping blades carried by said holders, one in advance of the other, counterbalaneed spring means for positioning said blades, said means comprising a spring device arranged between each of said holders and said frame and a spring device ar ranged between the two holders.

In witness whereof, l have hereunto signed my name this 11th day oit January 1908, in the presence of two subscribing witnesses.

ALBERT SCHlVENKE.

Witnesses JEAN GRUND, CARL GRUND. 

